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Sports and recreation

Running a marathon

Estimated population-level acute risk associated with completing a full marathon (26.2 miles) during a race event.

Base risk estimate

7 micromorts per races

Population-level estimate. Not a personal prediction.

Assumptions

Based on race-day conditions for competitive full marathon events (26.2 miles) in the United States 2000–2010. Includes cardiac events during and immediately after the race.

Limitations

Covers race-day cardiac risk only; does not include training-related events. Risk is substantially higher in men than women (0.90 vs 0.16 per 100,000 overall across all distances). Not applicable to recreational running at training pace or to half-marathon distances (~3 micromorts).

Source notes

Kim et al. studied 10.9 million participants in US marathon and half-marathon events 2000–2010, recording 59 cardiac arrests (42 deaths, 71% case fatality rate). The cardiac arrest rate for full marathons was 1.01 per 100,000 participants; applying the 71% case fatality rate yields approximately 0.72 deaths per 100,000 marathon finishers = ~7 micromorts per race.

Last reviewed

5/31/2024

RiskLens is an educational tool. It uses population-level estimates to help explain relative risk. It is not a prediction of your personal risk and should not be used as medical, legal, financial, or safety advice.